The present invention relates to a new and distinct variety of Prunus persica var. nucipersica yellow nectarine tree, which has been given the denomination ‘Nectapi’. This tree, named ‘Nectapi’, produces clingstone fruits of good eating quality for fresh market in early September in the 66—Pyrénées-Orientales departement—France. Contrast is made to ‘Nectalady’ (U.S. Plant Pat. No.17,580), ‘Maillardou’ (Bonbon®) (non-patented) and ‘Maillarboom’ (Big Boum®) (non-patented) yellow nectarine trees, standard varieties, for reliable description. ‘Nectapi’ is a promising candidate for commercial success in that it has an evenness of maturity, and produces regular fruits in large quantity and with a high productivity. It was chosen because of its hardiness and fruit lifetime before and after harvest, and because of its aromatic semi sweet taste.